Clamshell bucket



June H. E. DUNKELBERGER 1,365,091

CLAMSHELL BUCKET Filed July 30, 1931 2 Sheets-Sheet l M s s 09 Q0 M \N Mm r 8 w o W N w w WWW Mml m h\ QM m N N III N ,i @x k\ Fh-Tna EY June28, 1932. H. E. DUNKELBERGER 1,365,091

CLAMSHELL BUCKET Filed July so, 1951 2 Sheets-Sheet 2 INVENTUR PatentedJune 28, 1932 UNITED STATES HARRY E. DUNKELBERGER. or wnmron, wEs'rvmenim CLAMSHELL BUCKET Application filed Jul so, 1931. Serial No.553,909.

This invention relates broadly to dredging and loading apparatus, andmore specifically to grab-buckets of the so-called clam shell type.

The primary object of the invention is to provide a clam shell bucketwhich shall be specially strong and durable in its construction, whichshall be composed of a minimum number of parts, and which shall beparticularly efficient in operation.

A further object is to provide, in a bucket or scoop of the characterreferred to, a novel and improved lever arm whereon are mounted thesheaves through which closing of the bucket jaws is effected.

A still further object is to structurally improve and simplify existingforms of excavating and loading mechanisms of the type referred to. I

In describing the invention in detail, reference is herein had to theaccompanying drawings in which Figure 1 is a side elevation of a clamshell bucket embodying my invention, the bucket jaws being shown in openposition;

Figure 2 is a section on line 22, Fig. 1; Figure 3 is a top plan view ofthe bucket; and

Figure 4 is a section on line 44,Fig. 3.

' Referring'to said drawings, 1 and 2 designate generally cooperatingscoop members, or bucket jaws, which are pivotally related to permitrelative shifting thereof to and from closed load-carrying positions.Each of said bucket jaws comprises a pair of substantially parallel sidewalls 3 provided in V the form of heavy metal castings. Each of saidside-wall castings embodies, preferably as an integral part thereof, alongitudinally extending arm 3 Said arms have their inner ends formingbearing portions mounted for rotary movements upon the opposite endportions of a shaft or hinge pin 4 which con stitutes an axis for bothbucket jaws.

The parallel arms 3 of each bucket have their outer ends shaped toformheavy angularly disposed heads 5 which terminate in transversely alinedlips or flanges 6, and attached to said flanges by means of bolts orrivets are bottom plates 7 and 8 disposed substantially in theangular-relation shown. An adjustable wear-receiving blade 9 may beassociated with each bottom plate or element 8, as shown,but suchconstitutes no part of the invention herein claimed. 7

Eachof'the heads 5 of the arms 3 of the bucket jaw 1 has providedtherein a recess -in relatively spaced relation upon opposite ends of apivot pin let carried by the lower ends of links which, in turn, havetheir upper ends mounted on the opposite ends of a pivot pin 16 carriedmidway between the ends of a pair of horizontally disposed parallel arms17; and attached to the opposite ends of said arms 17 are the usualcables 18 by which the bucket and its load are suspended from the boomof the usual dredging, excavating, orloading machine.

Mounted in the head portions 13 of the suspension bars 11 in alinementwith the pivot pins 14 and 16 is a pivot pin 19, and pivotally mountedon the outer ends of said pin 19 are the upper ends of bars 20 by meansof which the outer, or bottom, end of the bucket jaw 2 is supported, thelower ends of said bars being received in the slots 10 provided, asaforesaid, in the heads 5 of the arms 3 of the bucket jaw 2 and beingattached to said heads by means of horizontally alined pivot pins 21.

Rigidly attached to the inner face of the bottom plate 7 of the bucketjaw l, as by means of bracket strips 22, are the rear ends of a pair ofheavy slabs 23 which, in the open position of the jaws 1 and 2, extendhorizontally across the top portion of the bucket and have theiropposite ends located at a suitably short distance from the bottom plate7 of the jaw 2. Said slabs, which occupy spaced parallel relation, havethe hinge-pin 4: extended therethrough with an end of a heavy bar-likemember 24 interposed therebetween. A hub-like bearing member 25 havingan end flange 26 is attached to the outer face of each slab 23, as bymeans of bolts or rivets 27 directed through said flanges 26, the slabs23 and the interposed end of the spacing member or counterbalance 24,such bolts or rivets maintaining said parts in fixed relation onsaid'hinge pin l. Said bearing members :25 abutthe adjacent bearingportions of the arms 3 of the bucket arms, spacing thelatter relative tothe said slabs.

The front end portions of the slabs 23, which together constitute alever arm, have mounted thereon a pluralityof sheaves 28 about which arepassed-the j awc'l.0sing cable 29. Said cable, whichleads from thewinding drum of the machine, is disposed in a plurality of passesbetween said sheaves 28 and a plurality of corresponding sheaves 30mounted on the pivot pin'19 between the head portions 13 of thesuspension bars 11 and has its end permanently attached to an anchor pin31 mounted in theislabs 23 of the lever arm at asuitable point,preferably adj acent to the hinge pin 4, as shown.

The bar-like member 2% hereinbefore referred to is designed asacounterbalance for the lever arm, being attached to and extendingforward between the slabs of the latter to or toward the front endsthereof. Additionally, said bar-like member, hereinafter referred to asa counterbalance, serves not only as means whereby said slabs orleverarm members 23am maintained rigidly in spaced relation, but va'lso'as-areinforcement for said lever arm. Said counterbalance is curved tounderlie said-sheaves 28 with sufficient clearance to avoid interferencewith the normal rotation of said sheaves. Obviously, the additionalweight thereby afforded to the front end of the lever arm is utilized,when the cable 29 is slacked, for facilitating automatic, orgravity-induced, actuation of the bucket jaws to their relativelyspread, or bucket opening, positions.

What is claimed is- 1. In a bucket of the character mentioned, a pair'ofbucket jaws, a:hinge pin upon which said jaws are relatively shif-table,:a lever arm mounted for rotary'movements on said hinge pin, said armcomp-rising relativelv spaced members attached at their rear en s 'toone of said bucket jaws, sheaves mounted between the front ends of saidarm members, and a counterbalance carried between said front ends inunderlying relation to said sheaves, said counterbalance having an endmounted on said hinge pin and forming a spacer for said arm members.

2. In a bucket of the character mentioned, a pair of bucket jaws, ahinge pin upon which said aws are relatively shiftable, a lever armmounted intermediate its ends upon and having rotary movement relativeto said hinge pin, said arm being formed of substantially parallel slabswhich have their rear ends fixed to one of said bucket jaws, acounterb-alancing member carried by the front end of said arm in spacingrelation to the slabs of the latter and having an end mounted on saidhinge pin, and sheaves carried by said arm over said counterbalancingmember.

3. In a bucket of the character'mentioned, a pair of bucket jaws, ahinge pin upon which said jaws are relatively shiftable, a lever armmounted for rotary movements on said hinge pin, said arm embodyingsubstantially parallel elements fixed at their rear ends to one of saidbucket aws and carrying sheaves upon their front ends, and acounterbalance mounted on the front end of said arm and maintaining theelements-of the latter in spaced relation, said counterbalance having anend rotatable with said arm on said hinge pin and being curved to affordclearance for the under peripheries of said sheaves.

4:. In a clam shell bucket, a hinge pin, a pair of bucket jawshaving'bearing portions mounted for rotary movements on said hinge pin,a lever arm comprising separate substantially parallel members mountedintermediate their ends for rotary movements on said hinge pin, spacingmembers interposed between said arm members and the adjacent bearingportions of said aws, and a counterbalance for said arm interposed inspacing relation to the front end portionsof the arm members and havingan end mounted on said hinge pin, andmeans-rigidly connecting said armmembers, said counterbalance and said spacing members.

5. In a clam shell bucket, a hinge pin, a pair of bucket jaws havingbearing portions mounted on said pin, a lever arm comprisingsubstantially parallel slab-like members mounted for rotary movement onsaid pin, and a lever arm counterbalance member mounted on said pin inspacing relation to said lever arm members and extending forwardlybetween the corresponding ends of and attached to the latter.

6. In a clam shell bucket, a hinge pin, a pair of bucket j aws havingbearing portions mounted on said pin, a lever arm comprisingsubstantially parallel slab-like members mounted for rotary movement onsaid pin, each of said members having attached thereto hub-like bearingswhich serve to space the lever arm relative to the adjacent bearingportions of the bucket jaws, and a counterbalance for said lever armmounted rigidly in spacing relation to the front end portions of themembers of the latter and having an end mounted on said hinge pin.

In testimony whereof, I afiix my signature.

HARRY E. DUNKELBERGER.

